Controllable phase shifter optimization control method and system based on sensitivity factor

Abstract

The invention discloses a sensitivity factor-based controllable phase shifter optimization control method and system, and belongs to the technical field of power grid operation optimization. The method comprises the following steps: firstly, based on a direct current power flow algorithm of a power grid, deriving a sensitivity factor of the influence of a controllable phase shifter on the transmission power of a key line; and secondly, on the basis of the sensitivity factor of the controllable phase shifter, constructing a controllable phase shifter control optimization model which aims at balancing the load rate of the key line, and performing calculation by adopting a linear least square method so as to obtain a final controllable phase shifter control scheme. Compared with a traditional method, the method is lower in calculation complexity under the condition that the control effect is guaranteed, and power grid operation optimization based on the controllable phase shifter is facilitated.

Description

Technical Field

[0001] The invention discloses a controllable phase shifter optimization control method, and in particular, relates to a controllable phase shifter optimization control method and system based on sensitivity factor. Background Art

[0002] With the access of new energy and energy storage to the power grid, the power grid operation faces more severe risks such as over-limit flow and power overload, and the power control of key lines in the power grid has become a key issue. In recent years, controllable phase shifters have attracted widespread attention due to their excellent power control capabilities, and how to give full play to the power regulation capabilities of controllable phase shifters in power grid operation has become a key issue.

[0003] For the study of controllable phase shifter control methods in power grids, simulation analysis-based methods are mainly used. However, the calculation process is often very complicated, requiring repeated iterations and low timeliness. The main challenge is that it is difficult to establish a direct correlation between the control variables of the controllable phase shifter and the operating status of the power grid when the controllable phase shifter is used in the power grid. Therefore, how to establish a direct correlation between the control variables of the controllable phase shifter and the operating status of the power grid is of great significance. Summary of the invention

[0004] The purpose of the present invention is to provide a controllable phase shifter optimization control method and system based on sensitivity factor, establish a direct correlation between the control variable of the controllable phase shifter and the operating state of the power grid, reduce the calculation complexity while ensuring the control effect, and help to achieve power grid operation optimization based on the controllable phase shifter.

[0005] The technical solution to achieve the purpose of the present invention is:

[0006] A sensitivity factor-based control method for optimizing a controllable phase shifter comprises the following steps:

[0007] Step 1, determine the key lines in the power grid;

[0008] Step 2, determining the installation line of the controllable phase shifter in the power grid;

[0009] Step 3, establishing a sensitivity factor calculation model for the influence of the controllable phase shifter on the power of the transmission section line;

[0010] Step 4, based on the sensitivity factor, construct a controllable phase shifter control mathematical model with the goal of balancing the critical line load rate;

[0011] Step 5, solving and calculating the control mathematical model of the controllable phase shifter, determining the control scheme of the controllable phase shifter, and performing power grid operation control of the controllable phase shifter.

[0012] Furthermore, the sensitivity factor calculation model of the controllable phase shifter on the power of the transmission section line is established, which specifically includes:

[0013] The key lines in the power grid are determined by the following formula:

[0014]

[0015] Among them, L line It is the key line mark, 1 means the line is a key line, 0 means the line is a non-key line. line and S line are the transmission power on the line and the line rated power respectively.

[0016] The installation line of the controllable phase shifter in the power grid is determined by the following formula:

[0017]

[0018] Among them, L set It is the mark of the controllable phase shifter installation line. 1 means that the line is a controllable phase shifter installation line, and 0 means that the line is not a controllable phase shifter installation line. ΔU loss and U N are the voltage loss on the line and the rated voltage of the line respectively.

[0019] For the scenario where the controllable phase shifter is connected in series to the line, when the controllable phase shifter is installed on the line between node i and node j, the power control sensitivity factor calculation model of line ij and any other line pq in the system except line ij is and for:

[0020]

[0021] Among them, y ij and pq are the elements (i, j) and (p, q) in the grid admittance matrix Y, p≠i, q≠j, which are determined by the grid structure and line parameters of the grid, k ij , k ii , k jj , k pj , k pi , k qi and k qj They are the inverse matrix K=Y of the grid admittance matrix -1 The elements (i,j), (i,i), (j,j), (p,j), (p,i), (q,i), and (q,j) in .

[0022] Furthermore, when the number of controllable phase shifters in the power grid is m and the number of key lines is l, the control mathematical model of the controllable phase shifter is:

[0023]

[0024] Where Z is the sensitivity factor and The sensitivity matrix composed of P is l×m in dimension. t and P0 are the control target value vector of the key route power and the power vector under the initial operation state, with a dimension of l×1. The power control target value p of the key route h h,t ∈P t , Δα is the control angle of the controllable phase shifter.

[0025] Furthermore, the power control target value p h,t for:

[0026]

[0027] Among them, p r,0 is the transmission power of the key line r in the initial operation mode, S h and S r are the rated capacities of key lines h and r respectively.

[0028] Furthermore, the control mathematical model of the controllable phase shifter is solved and calculated by the least square method.

[0029] A controllable phase shifter optimization control system based on sensitivity factor, comprising:

[0030] A sensitivity factor calculation unit calculates the sensitivity factor of the controllable phase shifter on the power of the transmission section line by establishing a sensitivity factor calculation model;

[0031] A controllable phase shifter control mathematical model building unit is used to build a controllable phase shifter control mathematical model with the goal of balancing the critical line load rate based on the sensitivity factor;

[0032] The control scheme determination unit solves and calculates the control mathematical model of the controllable phase shifter to determine the control scheme of the controllable phase shifter.

[0033] A controllable phase shifter optimization control device comprises: a memory, a processor and a computer program stored in the memory, wherein the processor implements the steps of the controllable phase shifter optimization control method when executing the computer program.

[0034] A computer storage medium stores an executable program, and the executable program is executed by a processor to implement the steps of the controllable phase shifter optimization control method.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] (1) The present invention proposes for the first time a sensitivity factor calculation method that can reflect the influence of a controllable phase shifter on line power, and can directly establish the correlation between the controllable phase shifter and line power;

[0037] (2) The present invention establishes a controllable phase shifter control optimization mathematical model with the goal of balancing the critical line load rate. The model can be calculated using the least squares method to avoid complex simulation calculation processes. The calculation process is simple and fast, thereby improving the simplicity and timeliness of the calculation. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 This is a flow chart of the optimization control method proposed in the present invention.

[0039] Figure 2 This is the New England 39-node system structure diagram. DETAILED DESCRIPTION

[0040] The present invention will be described in further detail below with reference to the accompanying drawings and in combination with embodiments. However, the present invention is not limited to the given examples.

[0041] The present invention establishes a direct correlation between the control variables of the controllable phase shifter and the operating state of the power grid. From the perspective of correlation sensitivity, a mapping relationship between the controllable phase shifter and the operating state of the power grid is established, thereby establishing a corresponding optimization model, avoiding complex simulation calculation processes, and improving the simplicity and timeliness of calculations. Figure 1 The present invention proposes a controllable phase shifter optimization control method based on sensitivity factor, which specifically includes the following steps:

[0042] (1) Determine the key lines in the power grid using the following formula;

[0043]

[0044] Among them, L line It is the key line mark, 1 means the line is a key line, 0 means the line is a non-key line; P line and S line are the transmission power on the line and the line rated power respectively

[0045] (2) Determine the installation line of the controllable phase shifter in the power grid by the following formula:

[0046]

[0047] Among them, L setIt is the mark of the controllable phase shifter installation line. 1 indicates that the line is a controllable phase shifter installation line, and 0 indicates that the line is not a controllable phase shifter installation line. ΔU loss and U N are the voltage loss on the line and the rated voltage of the line respectively.

[0048] (3) Based on the DC power flow algorithm of the power grid, the sensitivity factor of the controllable phase shifter on the transmission power of the key line is derived.

[0049] For the scenario where the controllable phase shifter is connected in series to the line, the controllable phase shifter can control the power angle change at both ends of the line to be α. When the controllable phase shifter is installed on the line between node i and node j, the power control sensitivity factor of line ij and line pq (any line other than line ij) is and The following formula is used for calculation:

[0050]

[0051] Among them, y ij and pq are the elements (i, j) and (p, q) in the grid admittance matrix Y, which are determined by the grid structure and line parameters of the grid. ij , k ii , k jj , k pj , k pi , k qi and k qj They are the inverse matrix K=Y of the grid admittance matrix -1 The elements (i,j), (i,i), (j,j), (p,j), (p,i), (q,i), and (q,j) in .

[0052] (4) Based on the sensitivity factor of the controllable phase shifter, a mathematical model for control optimization of the controllable phase shifter is constructed with the goal of balancing the load rate of the key lines.

[0053] When the number of controllable phase shifters in the power grid is m and the number of key lines is l, the control variable is the control angle Δα of the controllable phase shifter, and the control target is to minimize the difference between the transmission power of the key line and the target value. Its mathematical model has the following form:

[0054]

[0055] Where Z is the sensitivity factor and The sensitivity matrix composed of P is of dimension l×m. t and P0 are the control target value vector of the critical route power and the power vector under the initial operating state, with a dimension of l×1.

[0056] In the above mathematical model, the power control target value p of key line i is i,t ∈P t , set by the following formula:

[0057]

[0058] Among them, p i,t is the control target of the transmission power of key line i, p j,0 is the transmission power of key line j in the initial operation mode. i and S j are the rated capacities of key lines i and j respectively.

[0059] (5) The final mathematical model is solved and calculated using the least squares method to develop a control scheme for the controllable phase shifter.

[0060] A controllable phase shifter optimization control system based on sensitivity factor, comprising:

[0061] A sensitivity factor calculation unit calculates the sensitivity factor of the controllable phase shifter on the power of the transmission section line by establishing a sensitivity factor calculation model;

[0062] A controllable phase shifter control mathematical model building unit is used to build a controllable phase shifter control mathematical model with the goal of balancing the critical line load rate based on the sensitivity factor;

[0063] The control scheme determination unit solves and calculates the control mathematical model of the controllable phase shifter to determine the control scheme of the controllable phase shifter.

[0064] A controllable phase shifter optimization control device includes: a memory, a processor and a computer program stored in the memory, and the processor implements the steps of the controllable phase shifter optimization control method when executing the computer program. The memory may include a readable medium in the form of a volatile memory, such as a random access memory (RAM) and / or a cache memory, and may further include a read-only memory (ROM). The memory may also include a program tool having a group (at least one) of program modules, and the program modules include but are not limited to: an operating subsystem, one or more application programs, other program modules, and program data. Each of these examples or some combination may include the implementation of a network environment.

[0065] A computer storage medium stores an executable program, and the executable program is executed by a processor to implement the steps of the controllable phase shifter optimization control method. Specifically, the executable program can be built into a controllable phase shifter optimization control device, so that the controllable phase shifter optimization control device can implement the steps of the controllable phase shifter optimization control method of various exemplary embodiments of the present invention by executing the built-in executable program.

[0066] Compared with the traditional method, the present invention has lower calculation complexity while ensuring the control effect, which is helpful to realize the optimization of power grid operation based on the controllable phase shifter.

[0067] Example

[0068] Take the standard New England 39-node system as an example. Figure 2 As shown, according to the system operation mode data, the installation positions of the controllable phase shifters are calculated as lines 4-14 and 17-18, and the key lines of the system are lines 14-15, 17-18 and 25-26. Based on the basic line parameters of the New England 39-node system, the sensitivity factor matrix can be calculated as follows:

[0069] Table 1 Summary of controllable phase shifter control sensitivity factors

[0070]

[0071]

[0072] Furthermore, based on the basic power flow data of the New England 39-bus system and the calculated sensitivity factor value, the correlation between the key line transmission power and the control variable of the controllable phase shifter can be expressed as follows:

[0073] P L1 =0.1729+2.8298·α1+4.1834·α2

[0074] P L2 =1.3624+1.1230·α1+8.1499·α2

[0075] P L3 =0.0987-1.3311·α1+3.9665·α2

[0076] The control variable of the controllable phase shifter is radian rad; the key line transmission power is per unit value pu.

[0077] Based on the power flow data of the New England 39-node system, it is assumed that the rated capacities of lines 14-15, 17-18, and 25-26 are 1.5pu, 2.8pu, and 0.4pu, respectively. The load rates of lines 14-15, 17-18, and 25-26 are 11.52%, 48.66%, and 24.67%, respectively. To ensure that the load rates of the three key lines are the same, the control targets of the transmission power of lines 14-15, 17-18, and 25-26 are 0.525pu, 0.98pu, and 0.14pu, respectively. The proposed mathematical model is calculated using the least squares method, and the adjustment angles of the controllable phase shifter 1 and the controllable phase shifter 2 are 0.087rad and -0.0286rad, respectively. The load rates of the key lines before and after the control of the controllable phase shifter are shown in the following table.

[0078] Table 2 Key line power flow load ratio before and after controllable phase shifter control

[0079] Key line load factor Line 14-15 Line 17-18 Line 25-26 Basic operation mode 11.52％ 48.66％ 24.67％ After the controllable phase shifter is optimized 20.00％ 43.82％ 32.5％

[0080] It can be seen from the table that after the optimization of the controllable phase shifter, although the load rate of the key line cannot reach the target setting completely due to the limitations of the grid structure and operation mode, the power flow difference of the key line is significantly reduced, reflecting the effectiveness of the proposed method.

[0081] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0082] Obviously, those skilled in the art can make various changes and modifications to the embodiments of the present invention without departing from the spirit and scope of the embodiments of the present invention. Thus, if these modifications and variations of the embodiments of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A controllable phase shifter optimization control method based on sensitivity factor, characterized in that: Includes steps: Step 1, determine the key lines in the power grid; Step 2, determining the installation line of the controllable phase shifter in the power grid; Step 3, establishing a sensitivity factor calculation model for the influence of the controllable phase shifter on the power of the transmission section line; Step 4, based on the sensitivity factor, construct a controllable phase shifter control mathematical model with the goal of balancing the critical line load rate; Step 5, solving and calculating the control mathematical model of the controllable phase shifter, determining the control scheme of the controllable phase shifter, and optimizing the power grid operation of the controllable phase shifter.

2. The sensitivity factor-based control method for optimizing control of a controllable phase shifter according to claim 1, characterized in that: The key lines in the power grid are determined by the following formula: Among them, L line It is the key line mark, 1 means the line is a key line, 0 means the line is a non-key line; P line and S line are the transmission power on the line and the line rated power respectively.

3. The sensitivity factor-based control method for optimizing control of a controllable phase shifter according to claim 1, characterized in that: The installation line of the controllable phase shifter in the power grid is determined by the following formula: Among them, L set It is the mark of the controllable phase shifter installation line. 1 indicates that the line is a controllable phase shifter installation line, and 0 indicates that the line is not a controllable phase shifter installation line. ΔU loss and U N are the voltage loss on the line and the rated voltage of the line respectively.

4. The sensitivity factor-based control method for optimizing control of a controllable phase shifter according to claim 1, characterized in that: The calculation model of the sensitivity factor of the controllable phase shifter on the power of the transmission section line is established, which specifically includes: For the scenario where the controllable phase shifter is connected in series to the line, when the controllable phase shifter is installed on the line between node i and node j, the power control sensitivity factor calculation model of line ij and any other line pq in the system except line ij is and for: Among them, y ij and pq are the elements (i, j) and (p, q) in the grid admittance matrix Y, p≠i, q≠j, which are determined by the grid structure and line parameters of the grid, k ij , k ii , k jj , k pj , k pi , k qi and k qj They are the inverse matrix K=Y of the grid admittance matrix -1 The elements (i,j), (i,i), (j,j), (p,j), (p,i), (q,i), and (q,j) in .

5. The sensitivity factor-based control method for optimizing control of a controllable phase shifter according to claim 4, characterized in that: When the number of controllable phase shifters in the power grid is m and the number of key lines is l, the control mathematical model of the controllable phase shifter is: Where Z is the sensitivity factor and The sensitivity matrix composed of P is l×m in dimension. t and P0 are the control target value vector of the key route power and the power vector under the initial operation state, with a dimension of l×1. The power control target value p of the key route h h,t ∈P t , Δα is the control angle of the controllable phase shifter.

6. The sensitivity factor-based control method for optimizing control of a controllable phase shifter according to claim 5, characterized in that: The power control target value p h,t for: Among them, p r,0 is the transmission power of the key line r in the initial operation mode, S h and S r are the rated capacities of key lines h and r respectively.

7. The sensitivity factor-based control method for optimizing control of a controllable phase shifter according to claim 1, characterized in that: The mathematical model of controllable phase shifter is solved and calculated by the least square method.

8. A sensitivity factor-based controllable phase shifter optimization control system for implementing any of the methods described in claims 1-7, characterized in that: include: A sensitivity factor calculation unit calculates the sensitivity factor of the controllable phase shifter on the power of the transmission section line by establishing a sensitivity factor calculation model; A controllable phase shifter control mathematical model building unit is used to build a controllable phase shifter control mathematical model with the goal of balancing the critical line load rate based on the sensitivity factor; The control scheme determination unit solves and calculates the control mathematical model of the controllable phase shifter to determine the control scheme of the controllable phase shifter.

9. A controllable phase shifter optimization control device, characterized in that: include: A memory, a processor and a computer program stored in the memory, wherein the processor implements the steps of the controllable phase shifter optimization control method according to any one of claims 1 to 7 when executing the computer program.

10. A computer storage medium, characterized in that: The computer storage medium stores an executable program, and the executable program is executed by a processor to implement the steps of the controllable phase shifter optimization control method according to any one of claims 1 to 7.

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